NAME
Class::DBI::mysql - Extensions to Class::DBI for MySQL
SYNOPSIS
package Film;
use base 'Class::DBI::mysql';
__PACKAGE__->set_db('Main', 'dbi:mysql:dbname', 'user', 'password');
__PACKAGE__->set_up_table("film");
__PACKAGE__->autoinflate(dates => 'Time::Piece');
# Somewhere else ...
my $type = $class->column_type('column_name');
my @allowed = $class->enum_vals('column_name');
my $tonights_viewing = Film->retrieve_random;
DESCRIPTION
This is an extension to Class::DBI, containing several functions and
optimisations for the MySQL database. Instead of setting Class::DBI as
your base class, use this instead.
METHODS
set_up_table
__PACKAGE__->set_up_table("table_name");
Traditionally, to use Class::DBI, you have to set up the columns:
__PACKAGE__->columns(All => qw/list of columns/);
__PACKAGE__->columns(Primary => 'column_name');
Whilst this allows for more flexibility if you're going to arrange your
columns into a variety of groupings, sometimes you just want to create
the 'all columns' list. Well, this information is really simple to
extract from MySQL itself, so why not just use that?
This call will extract the list of all the columns, and the primary key
and set them up for you. It will die horribly if the table contains no
primary key, or has a composite primary key.
autoinflate
__PACKAGE__->autoinflate(column_type => 'Inflation::Class');
__PACKAGE__->autoinflate(timestamp => 'Time::Piece');
__PACKAGE__->autoinflate(dates => 'Time::Piece');
This will automatically set up has_a() relationships for all columns of
the specified type to the given class.
We currently assume that all classess passed will be able to inflate and
deflate without needing extra has_a arguments, with the example of
Time::Piece objects, which we deal with using Time::Piece::mysql (which
you'll have to have installed!).
The special type 'dates' will autoinflate all columns of type date,
datetime or timestamp.
create_table
$class->create_table(q{
name VARCHAR(40) NOT NULL PRIMARY KEY,
rank VARCHAR(20) NOT NULL DEFAULT 'Private',
serial INTEGER NOT NULL
});
This creates the table for the class, with the given schema. If the
table already exists we do nothing.
A typical use would be:
Music::CD->table('cd');
Music::CD->create_table(q{
cdid MEDIUMINT UNSIGNED NOT NULL PRIMARY KEY AUTO_INCREMENT,
artist MEDIUMINT UNSIGNED NOT NULL,
title VARCHAR(255),
year YEAR,
INDEX (artist),
INDEX (title)
});
Music::CD->set_up_table;
drop_table
$class->drop_table;
Drops the table for this class, if it exists.
column_type
my $type = $class->column_type('column_name');
This returns the 'type' of this table (VARCHAR(20), BIGINT, etc.)
enum_vals
my @allowed = $class->enum_vals('column_name');
This returns a list of the allowable values for an ENUM column.
retrieve_random
my $film = Film->retrieve_random;
This will select a random row from the database, and return you the
relevant object.
(MySQL 3.23 and higher only, at this point)
SEE ALSO
Class::DBI. MySQL (http://www.mysql.com/)
AUTHOR
Tony Bowden
BUGS and QUERIES
Please direct all correspondence regarding this module to:
bug-Class-DBI-mysql@rt.cpan.org
COPYRIGHT AND LICENSE
Copyright (C) 2001-2005 Tony Bowden.
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License; either version 2 of the License,
or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE.